Heavy oil upgrade method and apparatus

ABSTRACT

A method for upgrading a hydrocarbon in which an oxygen source and a hydrogen source are ignited and the resulting synthetic gas is used to initiate a predominantly gas phase heavy oil upgrade reaction. The upgrade reaction is quenched with an additional source of un-upgraded hydrocarbon.

CROSS-REFERENCE TO RELATED U.S. APPLICATION

[0001] This application claims priority benefit from U.S. ProvisionalApplication No. 60/285,212, filed on Apr. 20, 2001.

FIELD OF THE INVENTION

[0002] This invention relates to the upgrading of heavy oil into lightoil.

BACKGROUND OF THE INVENTION

[0003] A substantial portion of the world's oil reserves comprisebitumens, which are sometimes referred to as tar sands, and heavy crudeoils (collectively “heavy oil”). Heavy oil is difficult to produce, and,when produced, is difficult to market. Whether pipelines or shippingfacilities are used as the transportation medium, the cost oftransporting heavy oil is substantially higher than the cost for thetransporting of light oil. Once heavy oil is delivered at a receivingrefinery, more costly refinery processes are required to generateproducts suitable for the commercial marketplace. As a result, theeconomic value of heavy oil is lower than the value of light oil, andfor that reason a significant percentage of the world's heavy oilreserves remain underutilized.

[0004] To alleviate this underutilization problem, numerous methods havebeen proposed to upgrade heavy oil. Although the terms “heavy oil” and“upgrade” can be defined using several different technical parameters,one parameter that is frequently used to characterize the quality ofhydrocarbons is API gravity. Heavy oil is characterized by a generallylow API gravity, for example but without limitation in the range of API5 to API 25. Light oils have higher magnitude API gravities, for examplein the range API 35 to API 50. The term “upgrade” refers to the processof increasing the API gravity of oil from a relatively lower API gravityto a relatively higher API gravity. For example, but without limitation,oil can be upgraded from API 5 to API 15, or from API 30 to API 40.Upgrade is a relative term, and is not limited to a specific initial APIgravity value, or range, nor to a specific final API gravity value, orrange. Finally, the phrase “heavy oil upgrade reaction” refersgenerically to the chemical activities that occur in the process ofupgrading heavy oil.

[0005] Heavy oil upgrade methods sometimes involve pre-processing stepsintended to increase the efficiency of the heavy oil upgrade reaction.For example, U.S. Pat. No. 4,294,686 discloses the preliminarydistillation of the heavy oil stream into a light oil fraction and heavyoil fraction. The purpose of the preliminary distillation is to avoidthe unwanted cracking and coking of the light oil fraction that mightoccur if that fraction were included in the input stream to the upgradereactor. The light oil fraction that results is generally in a formsatisfactory either for use in the production facility as a fuel or fortransport to a refinery. However, preliminary distillation adds bothcost and complexity to the overall upgrade process, and is useful onlywhere the heavy oil is known to include a sufficient volume of lighthydrocarbons.

[0006] Other proposed upgrade methods include the pre-processing step ofmixing of an oil additive with the heavy oil. The resulting mixture isthen input to an upgrade reactor. For example, U.S. Pat. No. 6,059,957discloses the creation of an emulsion from the mixing of heavy oil andwater. That disclosure also provides for the optional inclusion of anemulsion-stabilizing surfactant. U.S. Pat. No. 6,004,453 discloses thecreation of a slurry from the mixing of a noncatalytic additive with theheavy oil. The publication of Moll, J. K. and Ng, F.T.T., “A NovelProcess for Upgrading Heavy Oil/Bitumen Emulsions Via In Situ Hydrogen,”16th World Petroleum Congress, Calgary, Canada, June 2000, discloses useof an emulsion from a water-soluble dispersed catalyst. Each of thesethree methods has two general limitations however. First, the mixingstep adds both cost and complexity to the overall upgrading process.Second, the additives cause the creation of waste materials during theupgrade reactions that must thereafter be appropriately processed anddisposed. That processing and disposal also adds cost and complexity.

[0007] A third set of heavy oil upgrade methods include the step ofusing a reaction additive in the upgrade reactor to facilitate, orimprove the efficiency of, the upgrade reaction. For example, thepublication of Paez, R., Luzardo, L., and Guitian, J., “Current andFuture Upgrading Options for the Orinoco Heavy Crude Oils,” 16th WorldPetroleum Congress, Calgary, Canada, June 2000, discloses the use ofcoke or iron-based catalysts in the upgrading process. Disclosure WO00/61705 discloses the use of a non-catalytic particulate heat carrier.U.S. Pat. No. 5,817,229 discloses the use of activated carbon, in theabsence of added hydrogen, to both reduce the content of undesirableminerals and to upgrade the quality of the input crude. These methodshave both of the limitations of the oil additive methods discussedabove, namely added cost and complexity and increased waste materialprocessing requirements.

[0008] The hydrogenation method of U.S. Pat. No. 5,069,775 reactshydrogen and heavy oil for from five minutes to four hours in apreferred reaction temperature range of 800 to 900° F. (427 to 482° C.).U.S. Pat. No. 5,269,909 discloses a method whereby a gas rich in methaneis reacted with heavy oil for at least thirty minutes in a preferredtemperature range of 380 to 420° C. (716 to 788° F.). The method of U.S.Pat. No. 5,133,941 flows hydrogen and heavy oil through sequentiallyconnected reaction passageways in a preferred temperature range of 700to 900° F. (371 to 482° C.). As will be understood to those skilled inthe art, a limitation of these methods is that the generally longreaction durations cause a substantial increase in the generation ofundesirable waste materials, specifically pitch, coke, and olefins.These materials create significant disposal challenges for theprocessing facility, and, in addition, lead to a reduction in theefficiency of the facility.

[0009] Disclosure WO 00/18854 discloses a two-part process in whichhydrogen gas is mixed with heavy oil in a manner that attempts toachieve molecular level dispersion of hydrogen throughout the heavy oil.The method has a first upgrade reaction that separates the lighterhydrocarbons from the heavy oil, and continues with a second upgradereaction in a second reactor. The second upgrade reaction furtherupgrades the heavy oil via a hydrogenation reaction within a preferredtemperature range of 343 to 510° C. (650 to 950° F.). The methodincludes the added step of providing externally supplied heat to thehydrogen-heavy oil mixture to further facilitate the reaction in thesecond reactor. Limitations of this process include the difficulty ofachieving the required uniform mixing of hydrogen and heavy oil, and thecost and complexity of implementing a process that requires two reactionsteps.

[0010] These and other previously proposed upgrade methods suffer froman inherent limitation that has long plagued industry. On one hand, itis well known to those skilled in the art that upgrade reactions arepreferably carried out at the highest possible reaction temperature,since upgrade processes are more efficient at higher temperatures.Unfortunately, as is also well known to those skilled in the art, highreaction temperatures can lead to significant unwanted cracking andcoking of the heavy oil molecules if the reactions are not quicklyquenched. None of these methods have a mechanism for quickly quenchingthe reactions and they are therefore constrained to lower temperatureoperating ranges. On the other hand, however, reaction durations arelonger at lower temperatures, and it is equally well known that longreaction also lead unwanted cracking and coking, and, in addition, tolower process efficiencies due to the extra time required for theupgrade. These methods are therefore constrained to a compromisetemperature range that is a tradeoff between these limitations.

[0011] WO 00/23540 discloses a method in which a jet of gas, comprisingessentially of superheated steam, activates the upgrading of the heavyoil. The method has a number of limitations. Using steam as thehydrogenation mechanism means that both hydrogen and oxygen-hydrogenradicals are generated in the upgrade reactions. As a result, fewerhydrogen molecules are available, in comparison to processes in whichhydrocarbon-based gases are predominantly used, to saturate the carbonradicals created from the heavy oil carbon bond breaking. In addition, alarge volume of superheated steam is required. Because steam generationis endothermic, this constraint is costly, self-limiting, and inherentlyinefficient—fuel is consumed to generate steam, but the energy in thatsteam is only passively used to provide a thermal input to the upgradingof the heavy oil. Thus energy losses are incurred both in the generationof the steam and in the passive upgrade. This limits the efficiency ofthe upgrading process.

[0012] Another limitation of WO 00/23540 is that the bonding ofoxygen-hydrogen radicals from the steam with carbon radicals from theheavy oil creates an output product in an emulsion form. Emulsions are aless desirable product at refineries due to the need to handle theincreased volume of produced water that results during the refiningprocess. Emulsions also add the requirement for a post-reaction soakingdrum to ensure stabilization of the output products. Because soakerscannot quickly quench upgrade reactions or actively controlstabilization times, this limitation leads to the creation of pitch andother unwanted waste materials.

[0013] Finally, WO 00/23540 is also constrained by the use of steam asthe predominant hydrogenation source for the upgrade reaction. Steamcauses side reactions that cannot be completely inhibited except under anarrow range of pressure and temperature conditions. Outside that range,unwanted gases and waste products are generated, and the output productsuffers a loss of stability. As a result, reaction temperatures aregenerally limited to 500° C. (932° F.) or less, another efficiencyconstraint.

[0014] It is apparent that a need exists for a method that can becarried out without a preliminary distillation step, and without the useof oil or reaction additives. The method should avoid unwanted crackingand coking of the heavy oil, and minimize the production of undesirablewaste materials. The output product should not be an emulsion. Theupgrade efficiency of the method should not require uniform dispersionof hydrogen or other input gas throughout the heavy oil, or requirerelatively long exposure durations of the input gas to the heavy oil.

[0015] Furthermore, a need exists for a method that can preferably becarried out at high temperatures, to thereby facilitate short reactiontimes and high upgrade efficiencies. The method should involve a directmechanism of transferring the heat input to the heavy oil to beupgraded. The method should include an active mechanism for quicklyquenching the upgrade reactions. The present invention satisfies theserequirements.

SUMMARY

[0016] This invention relates generally to the upgrading of liquidhydrocarbons. Specifically, this invention relates to a method forupgrading a hydrocarbon in which an oxygen source and ahydrocarbon-containing fuel mixture are ignited. Heat generated by thatignition vaporizes a portion of the hydrocarbon and initiates apredominantly gas phase upgrade reaction.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The features of the present invention will become more apparentfrom the following description in which reference is made to thedrawings appended hereto. Reference numbers that are used in more thanone of the drawings refer to the same function in each drawing.

[0018]FIG. 1 is a sectional-view of an embodiment of an injectionreactor that may be used in the method of the present invention.

[0019]FIG. 2 is a schematic representation generally illustrating oneembodiment of a heavy oil upgrade method of the present invention.

[0020]FIG. 3 is a more detailed schematic representation of the heavyoil upgrade method illustrated in FIG. 1, with an expanded illustrationof heat exchanger and separation equipment.

[0021]FIG. 4 is similar to FIG. 3, except that recycled unreacted heavyoil is added to the input to the injection reactor of the method of thepresent invention.

[0022]FIG. 5 is a schematic representation illustrating an embodiment ofa partial oxidation reactor that may be used in the method of thepresent invention, with an expanded illustration of heat exchanger andseparation equipment.

[0023]FIG. 6 is similar to FIG. 5, with the addition of recycled tailgas as an input to the partial oxidation reactor.

[0024] Changes and modifications in the specifically describedembodiments can be carried out without departing from the scope of theinvention, which is intended to be limited only by the scope of theappended claims.

DETAILED DESCRIPTION OF THE INVENTION

[0025] The present invention is directed to the upgrading of heavy oil,and is often referred to as the “Partial Crude Upgrading” (“PCU”)process. The PCU process can upgrade oil in one step, without the needfor a preliminary distillation or for oil or reaction additives. Theseadvantages increase the simplicity and lower the cost of the PCU processin comparison to previously proposed heavy oil upgrade techniques.

[0026] The PCU process rapidly heats heavy oil, thereby quickly breakingcarbon bonds in the heavy oil molecules. This characteristic shortensthe time required for the overall upgrade process and increases theefficiency of the entire upgrade facility. The reactions are quicklyquenched by unreacted, in other words un-upgraded, heavy oil. Thisactive quenching technique reduces both the amount of coking thattypically occurs when upgrade reactions are not quickly controlled andthe production of other unwanted waste materials.

[0027] The upgrade reaction for the PCU process is initiated by theinjection of compressed air and a fuel mixture into a reactor vessel.Extremely high reaction temperatures result from the ignition of thosegases by igniters in the injectors. These temperatures result from anexothermic reaction that releases a high amount of energy for thevaporization of, and cracking of the molecular bonds in, the heavy oilmolecules. The heavy oil upgrade results from the exposure of the heavyoil molecules to the energy released by the exothermic reaction. Theexothermic generation of energy is an important aspect of the presentinvention in comparison to previous methods, because an increased amountof energy thereby becomes available for the breaking of the molecularbonds in the heavy oil.

[0028] The energy in the PCU process results from the partial oxidationreaction of compressed air with the fuel mixture. The compressed airacts as the oxidizing agent and the fuel mixture as the hydrogen sourcein the reaction which creates a synthetic gas, referred to as syngas.The creation of syngas allows high temperatures to be exothermicallycreated for the upgrade reaction, and shortens upgrade reaction timescompared to previously proposed upgrade techniques. Syngas also containsreactive gas components that facilitate the upgrade reaction, andpreferably generates an oversupply of hydrogen radicals for bonding withcarbon radicals created by the upgrade reactions. Having carbon radicalsbond with hydrogen rather than with other undesirable radicals, a resultwhich typically occurs from the use of gases which are predominantlycomposed of superheated steam, reduces the likelihood that the outputproduct will be an undesirable emulsion or that coke, pitch and unstableolefins will be created.

[0029] Gaseous hydrocarbons, such as natural gas, are the preferredfuels to generate syngas, because of their high concentration ofhydrogen. However, either liquid fuels or heavy oil feeds may be used insyngas generation. Furthermore, either air, enriched air (e.g. airenriched with additional oxygen), or pure oxygen may be used as theoxygen source. The reactor vessel within which the heavy oil crackingand quenching takes place may operate at pressures below 700 psig (4,928kPa), and more preferably may be operated at pressures below 400 psig(2,859 kPa).

[0030] The reactions are quenched in the same reactor vessel usingunreacted heavy oil, which is at a lower temperature than is theupgraded heavy oil. Quenching occurs shortly after exposure of the heavyoil to the syngas. Control of the reactor pressures, and the rate ofinput of air, fuel, and unreacted heavy oil, provides for a method ofcontrolling the rate at which the reactions are quenched.

[0031] The PCU process facilitates synergies between fuel and heatintegration and the production facilities. Fuel gas produced by the PCUprocess may be used to generate high-pressure steam, which may be used,for example, to assist heavy oil production or to preheat the feeds tothe reactor vessel. Alternatively, the fuel gas may be fed to gasturbines to generate power to support the production facility.

[0032]FIG. 1 depicts an embodiment of an injection reactor that may beused in the method of the present invention. In FIG. 1, injectionreactor 14 consists of outer walls 32, upper wall 41, and lower wall 45,with ignition injector 30 centrally installed within injection reactor14. The embodiment of FIG. 1 is simplified for descriptive purposesonly. For example, ignition injector 30 is depicted in an oversizedimension compared to injection reactor 14. As will be understood tothose skilled in the art, one or more ignition injectors will beemployed in injection reactor 14 to achieve generally uniform upgradereactions and reaction quenching, and the dimensional proportions ofignition injector 30 compared to injection reactor 14 will be determinedfrom the intended throughput capacity of the upgrade facility.

[0033] The embodiment of ignition injector 30 in FIG. 1 is similar to aneduction-type mixing nozzle, preferably made with high-temperatureresistant alloys, which has been fitted with a centrally located igniter42. Ignition injector 30 comprises injector wall 34, and injector base36. Injector base 36 is connected to injector wall 34 by injector struts38. In this embodiment injector base 36 is connected to lower wall 45 ofinjection reactor 14 by screw threads. It will be understood that themethod of the present invention is not limited to the use of ascrew-thread connection, nor to connection of ignition injector 30 atthe base of injection reactor 14, nor to the location of inlets 47 andoutlet 49, which allow flow into and out of the top and bottom ofinjection reactor 14, respectively, and that the geometry in FIG. 1 hasbeen chosen for exemplary purposes only. Injector conduit 40 iscentrally located within injector base 36. Igniter 42 in turn iscentrally located within injector conduit 40.

[0034] Heated compressed air 12 is fed into reaction chamber 44 throughair input annulus 39 created between injector conduit 40 and igniter 42.Igniter 42 may be any hot-surface or sparking igniter that providesreliable ignition of gases. Heated fuel mixture 9 is fed into reactionchamber 44 through fuel input annulus 37 created between injector base36 and injector conduit 40. Heavy oil is input into reaction chamber 44through input slots 35, which are openings between injector struts 38which allow flow from outer annulus 33 between outer wall 32 andignition injector 30 to reaction chamber 44.

[0035] Tip 43 of igniter 42 ignites heated compressed air 12 and heatedfuel mixture 9 to create high temperature syngas in the lower portion ofreaction chamber 44 adjacent to struts 38. Heated heavy oil 2 flows intoinjection reactor 14 through inlets 47 in lower wall 45 and entersreaction chamber 44 through input slots 35 of ignition injector 30 and,upon contact with high temperature syngas, is rapidly subjected to aheavy oil upgrade reaction within reaction chamber 44. The flow ofheated heavy oil 2 through input slots 35 results from an eduction forcecreated from the mass momentum generated from the ignition of the gasesthat generates the syngas. The rapid heavy oil upgrade reaction resultspredominantly from the vaporization of a portion of heated heavy oil 2when heated compressed air 12 and heated fuel mixture 9 are ignited,however, an heavy oil upgrade reaction will also occur within anyunvaporized heavy oil within reaction chamber 44. Both the vaporized andany unvaporized upgraded heavy oil flow out of reaction chamber 44 intomixing chamber 46, which is the open area in injection reactor 14 belowupper wall 41 but above ignition injector 30. To prevent undesirablesecondary reactions, the heavy oil upgrade reaction is rapidly quenchedby mixing the outflow of reaction chamber 44 with additional heatedheavy oil 2 in mixing chamber 46. The additional heated heavy oil 2flows through reactor annulus 33 to mixing chamber 46. The resultingupgraded oil mixture 3 flows out of upper wall 41 of injection reactor14 through outlet 49 by pressure drive after a residence time in mixingchamber 46, preferably of 1 to 60 minutes, and more preferably 2 to 20minutes, which further stabilizes upgraded oil mixture 3. Injectionreactor 14 may operate under mild pressures, generally below 700 psig(4,928 kPa) and preferably below 400 psig (2,859 kPa).

[0036] The syngas generated within reaction chamber 44 will generallyhave a temperature above 1200° F. (649° C.), preferably within the rangeof 1200 to 3000° F. (649 to 1,649° C.) and more preferably within therange of 1400° to 2400° F. (760 to 1,316° C.), to rapidly upgrade heatedheavy oil 2. Natural gas is the preferred fuel for syngas generation dueto its high hydrogen content. The term natural gas refers generally togaseous hydrocarbon mixtures, for example containing such components asmethane, ethane, and propane. Natural gas may also contain sulphur andtrace amounts of various metals. However, any hydrogen-containing fuelsource, such as liquefied petroleum gas or naphtha, may be used as fuelfor syngas generation. Alternatively heavy feeds such as the heavy crudeitself, petroleum residual oils and cokes may be used to generate syngasfor upgrading.

[0037] The reaction time in reaction chamber 44 will preferably be tenseconds or less, and more preferably less than 2 seconds, to limitsecondary cracking reactions. The velocities of heated fuel mixture 9and heated compressed air 12 into reaction chamber 44 should preferablybe relatively high to prevent damage to ignition injector 30 from theignition reaction that creates the syngas. A minimum velocity of 10ft/sec (3 m/s) is preferred, although, depending on the alloy from whichignition injector 30 is fabricated, lower velocities may be used.Depending on the velocities used, the reaction zone of the heavy oilupgrade reaction may extend beyond the lower portion of reaction chamber44, and possibly into chamber 46.

[0038] A preferred ignition injector is an eduction-type injectionnozzle, as depicted in FIG. 1, that has a conical shaped chamber tofacilitate both the ignition of heated compressed air 12 and heated fuelmixture 9, and the cracking of the heavy oil molecular bonds. In thedesign depicted in FIG. 1, with a centrally-located igniter installedwithin the injection nozzle, the partial oxidation reaction is believedto primarily occur at the center of reaction chamber 44, with a portionof heated heavy oil 2 flowing along the inner surface of injector wall34, thereby serving as a protective film for the inside surface ofinjector wall 34.

[0039] It will be understood that injector 30 and igniter 42 are notnecessarily limited to the geometry of the embodiment depicted inFIG. 1. Although a coannular-type injector is preferred to achieve fastignition of the fuel and air mixture and to avoid flashback, anyinjection igniter that is capable of generating syngas without injectordamage can be used. Furthermore, instead of inputting heated compressedair 12 and heated fuel mixture 9 through concentric annuli withininjector base 36, separate input lines could used to input heatedcompressed air 12 and heated fuel mixture 9 into reaction chamber 44.Similarly, heated heavy oil 2 could be input through a separate,nonconcentric input line. Depending on the geometry and length ofinjector wall 34, heated heavy oil 2 could be input to the upper portionof reaction chamber 44 through slots in the top of injector wall 34,thereby further facilitating the reaction quenching. Each of theexamples in this paragraph are not depicted in FIG. 1, but will beunderstood to one skilled in the art, who will also recognize otherimplementation examples of suitable ignition injectors based on theteachings of this description.

[0040]FIG. 2 depicts a simplified schematic of one embodiment of the useof injection reactor 14 in the method of the present invention. Heavycrude 1 from any source is preheated in heat exchanger 13 to generateheated heavy oil 2, which is input into injection reactor 14. Thetemperature of heated heavy oil 2 is preferably low enough to minimizethermal cracking of the oil molecules, and for most heavy oil will rangefrom 300 to 800° F. (149 to 427° C.), and more preferably from 400 to600° F. (204 to 316° C.).

[0041] Air 10 is compressed in air compressor 15. Compressed air 11 isheated in furnace 17 to a temperature preferably between 500 and 1500°F. (260 to 816° C.), and more preferably between 500 and 1200° F. (260to 649° C.). Heated compressed air 12 is then input to injection reactor14. As noted above, other sources of oxygen molecules may be used. Itwill be understood that preheating of heavy crude 1 or compressed air 11are not requirements of the present invention, but are preferable toincrease the efficiency of the upgrade reaction. Steam 7 is created fromthe heating of boiler feed water 6 in furnace 17. Natural gas 5 mixeswith steam 7 in mixer 16, and is heated in furnace 17 to a temperaturepreferably between 500 and 1200° F. (260 to 649° C.). The heated fuelmixture 9 that results is input to injection reactor 14.

[0042] As described above in conjunction with FIG. 1, ignition of heatedcompressed air 12 and heated fuel mixture 9 in the presence of heatedheavy oil 2 initiates the upgrade reaction. It is preferable if multipleignition injectors 30 are uniformly spaced within injection reactor 14to facilitate the maximum throughput and efficiency of the upgradefacility. The exact number of ignition injectors 30 will depend on thesize of injection reactor 14 and the desired throughput volume of theupgrade facility. Also as described above, the output of injectionreactor 14 is upgraded oil mixture 3.

[0043] A small amount of solid materials, preferably less than fiveweight percent, may optionally be mixed (not shown in the drawings) withheated heavy oil 2 before it is input to injection reactor 14 to controlpotential deposits within injection reactor 14. These solids can beeither inert, such as sand, or reactive, such as coal.

[0044] In this embodiment, upgraded oil mixture 3 is used as a heatsource for heat exchanger 13. Cooled upgraded heavy oil 4 is then inputto a conventional separator 18, which produces product crude 21, fuelgas 19, sulfur product 20, and waste water 2.

[0045] To fully appreciate the present invention, it is useful tocontrast the PCU process with the manner in which previously proposedmethods upgrade heavy oil. The variety of previously proposed methodshave been directed to a liquid phase heavy oil upgrade reaction in whichthe molecular bonds in liquid phase heavy oil are broken and theresulting carbon radicals combined with available hydrogen radicals tocreate a stabilized upgraded heavy oil.

[0046] In contrast, the PCU process focuses on a predominantly gas phaseheavy oil upgrade reaction. Specifically, heat released during theformation of syngas vaporizes a portion of heavy oil, thereby allowing agas phase heavy oil upgrade reaction to occur. This vaporization and gasphase reaction occurs much more quickly than does a liquid phasereaction, with the hydrogen within the syngas simultaneously availableto bond with the heavy oil's carbon atoms. Although the process may becarried out at high pressures, high pressures are not necessary tofacilitate this gas phase reaction, thereby allowing lower pressures tobe used if desired. In addition, hydrogen and carbon molecules bond morereadily in the gas phase, further facilitating short upgrade reactiontimes and high upgrade process efficiencies.

[0047] Because the PCU process' gas phase upgrade reaction occursquickly, a method of rapidly quenching the upgraded heavy oil is alsonecessary. Because the temperature differential between the upgradedvaporized heavy oil and the un-upgraded heavy oil is large, additionalun-upgraded heavy oil quickly quenches the upgrade reaction and therebyprevents the generation of unwanted waste materials. The temperaturedifferential is much less in liquid phase techniques, and therefore thereactions in those techniques cannot be quenched as quickly and unwantedwaste materials cannot be avoided to the same extent as in the PCUprocess.

[0048] Applicant's invention takes advantage of presently availablecomponents to facilitate fabrication of reliable heavy oil upgradefacilities. For example, ignition injector 30 must allow air and fuel toflow into reaction chamber 44. This requirement can be met by nozzleswhich have long been used to circulate and mix fluids in closed and opentanks. One example of nozzles which may be modified to meet therequirements of ignition injector 30 are the TurboMix™ products of BETEFog Nozzle, Inc. of Greenfield, Mass. Similarly, igniter 42 may be basedon hot surface igniters which have long been used in gas appliances. Forexample, the MINI-IGNITER line of products of Saint-Goban/AdvancedCeramics-Norton Igniter Products of Milford, Mass. could be modified tomeet the needs of the PCU process. Advantages of hot surface igniters,as compared to sparking-type igniters, include low input powerrequirements and safer operation. The ability of Applicants' inventionto build on presently available technologies and component parts—in eachcase from diverse and previously unrelated areas of commerce—is a uniquecharacteristic of the PCU process and an important advance overpreviously proposed heavy oil upgrade processes.

[0049] In distinguishing the PCU process from previously disclosedmethods, applicants are not bound by any specific physical, chemical, ormechanical theory of operation. Applicants have set forth these theoriesin an effort to explain how and why the invention is believed to work.These theories are set forth for informational purposes only, and arenot to be interpreted as limiting in any way the true spirit and scopeof the present invention.

[0050] A second embodiment of the PCU process is shown in FIG. 3. Thisembodiment provides an example of the upgrade efficiencies that resultfrom implementation of the PCU process. In FIG. 3 the operation of heatexchanger 13, injection reactor 14, air compressor 15, mixer 16, andfurnace 17 are as described above.

[0051] In this configuration, upgraded oil mixture 3 is subjected to asecond heat exchanger 50 for further cooling before being input ascooled upgraded heavy oil 4 to gas-liquid separator 51. An efficiency ofthis implementation is that boiler feed water 6 can be used as thecooling medium for heat exchanger 50, with heated boiler feed water 23then being input to furnace 17. The result is a second source of waterto furnace 17 to generate steam 7, or, alternately, to generate aseparate high-pressure steam supply 24 for such applications as enhancedoil recovery.

[0052] Gases separated from gas-liquid separator 51 are sent through anexpansion device, such as a Joule-Thomson valve, 53 and mixer 54 beforebeing input as gas 67 to gas treating unit 57. The output of gastreating unit 57 is fuel gas 19 and sulfur product 20. In thisembodiment, sulfur product 20 will most likely be hydrogen sulfide gas,as will be understood to those skilled in the art. As a result, productcrude 21 will have a lower sulfur content than does heavy oil 1. Anotherefficiency of this embodiment is that fuel gas 19 can be used as powersource for furnace 17, and, or in the alternative, as power source forturbine 60 to generate power 61.

[0053] Liquids separated from gas-liquid separator 51 are sent throughexpansion device 52 to generate liquid product 66, which is input toliquids separator 55. Waste water 22, if generated, results from liquidsseparator 55. Any extraneous gas 74 not previously separated is sent tomixer 59, where it mixes with gas withdrawn from stripping tower 58.That mixture is compressed in tail gas compressor 56, and input to mixer54. Hydrocarbon liquids 65 from separator 55 are sent to stripping tower58 to generate product crude 21.

[0054] Process simulations of the PCU process have been carried out.Numerous process simulation-modeling programs are commerciallyavailable; one example is the HYSYS™ program, version 2.2, a product ofHyprotech Ltd., a subsidiary of AEA Technology plc. Other such programswill be known to those skilled in the art. Table 1 provides typicaloperating temperatures, pressures, and flow rates at various stages ofthe PCU process, and is cross-referenced to the reference numbers inFIG. 3. For simplicity, the process simulation results depicted in Table1 used an assumed mixture of heavy paraffins and sulfur-containingparaffinic compounds to represent heavy oil 1. Specifically, a mixtureof 50% of n-C₃₀H₆₂ and 50% of n-C₃₀H₆₁SH was assumed to represent heavyoil. The simulations assumed that a 40% portion of the heavy oil inputstream reacted with syngas for complete conversion into cracked productsvia the following two reactions:

n-C₃₀H₆₁SH+H₂ →n-C₃₀H₆₂+H₂S  (1)

n-C₃₀H₆₂ +xH₂→Cracked products  (2)

[0055] The cracked products were assumed to be mixture of compoundshaving individual carbon sequences ranging from 1 to 22 carbon moleculeslong. The assumed cracking chemistry yields 6.6% of gases with one tofour carbon molecules and the overall hydrogen consumption is 268scf/bbl. Sensitivity tests were performed for mixtures having assumedcarbon sequences ranging from 1 to 28 molecules long, and with acracking gas yield of 4.7% and overall hydrogen consumption of 230scf/bbl, without substantial differences from the results summarizedbelow.

[0056] The simulation assumed that 10% of the carbon monoxide within thesyngas reacts with water to form additional hydrogen molecules forbonding with the heavy oil radicals. The simulation assumed that theunreacted 60% of the heavy oil input stream was used to quench theupgrade reaction.

[0057] The simulation results in Table 1 demonstrate the benefits of thePCU process. The 0.6 ratio of steam 7 to natural gas 5 is lower than isrequired in previously disclosed heavy oil upgrade techniques. As aresult, the process generates a low volume of wastewater 22. Inaddition, product crude 21 does not suffer output volume reductions thatare typical of many heavy oil upgrade techniques. Product crude 21,which consists of a mixture on a mole-percent basis of 61.8% of crackedheavy oil components and 38.2% of uncracked heavy oil, has been upgradedby API 6.8 in comparison to heavy oil 1. TABLE 1 Simulation Results forPCU Process Embodiment of FIG. 3 Oil Process Flow Flow VolumeTemperature Temperature Pressure Pressure Quality Reference VolumeKgmole/hr ° F. ° C. psia Kpa API Heavy Oil 1 40,000 528.4 199.5 93.1 1691,165 32.8 bbl/day Natural Gas 5  9.1 mscf/day 453.6 80 26.7 178.5 1,231Input to Mixer 16 Steam 7  10,810 lb/hr 272.2 372.8 189.3 178.5 1,231Heated Boiler 551,000 lb/hr 13,870 357.2 180.7 1520 10,480 Feed Water 23Heated  96,400 lb/hr 1,518 1050 565.6 177 1,220 Compressed Air 12 HeatedFuel  27,830 lb/hr 725.8 1050 565.6 177 1,220 Mixture 9 Syngas 124,230lb/hr 2,768 2237 1,225 167 1,151 Generated within Injection Reactor 14Heated Heavy 40,000 528.4 500 260 167 1,151 Oil 2c bbl/day UpgradedHeavy 635,400 lb/hr 3,295 752.8 400.2 160 1,103 Oil 3 Cooled Upgraded635,400 lb/hr 3,295 120 48.9 112.5 776 Heavy Oil 4 Liquid Product 66507,600 lb/hr 1,255 118.9 48.3 14.8 102 Sour Crude 65 40,840 846.1 118.948.3 14.8 102 bbl/day Natural Gas 5 910 kscf/day 45.4 692 20.7 15.8 109Input to Stripping Tower 58 Gas 67 135,600 lb/hr 2,147 110 43.3 45 310Wastewater 22  991 363.6 118.9 48.3 14.8 102 bbl/day Exhaust Gas  279mscf/day 13,880 505.8 263.2 14.8 102 from Furnace 17 Product Crude 2140,620 829.3 117.4 47.4 15.8 109 39.6 bbl/day

[0058]FIG. 4 depicts an embodiment of the PCU process similar to theembodiment of FIG. 3, except that distillation tower 62 replacesstripping tower 58 and a portion of unreacted heavy oil 25 is recycledback to injection reactor 14 by mixing with heavy oil 1 in mixer 63. Insimulations of this embodiment 20% of the unreacted heavy oil fromdistillation tower 62 is recycled, although the embodiment is notlimited to the recycling of any specified percentage of unreacted heavyoil from the distillation tower. Mixed heavy oil 26 is heated in heatexchanger 13 before being input to injection reactor 14. The simulationagain assumes 40% of the heated heavy oil 2 reacts with syngas and theremaining 60% is the quenching material. The results of the simulationof this embodiment are depicted in Table 2. Note that product crude 21has a significantly higher API gravity than in the embodiment of FIG. 3.In this embodiment product crude 21 contains 66.9 mole-percent crackedheavy oil components. TABLE 2 Simulation Results for Recycled Heavy OilPCU Process Embodiment of FIG. 4 Oil Process Flow Flow VolumeTemperature Temperature Pressure Pressure Quality Reference VolumeKgmole/hr ° F. ° C. psia Kpa API Heavy Oil 1 40,000 528.4 199.5 93.1 1691,165 32.8 bbl/day Recycled Heavy  5,454 72.0 200 93.3 169 1,165 Oil 25bbl/day Natural Gas 5 10.4 517.1 80 26.7 178.5 1,231 Input to Mixer 16mscf/day Steam 7  12,320 lb/hr 310.3 372.8 189.3 178.5 1,231 HeatedBoiler 626,500 lb/hr 15,770 357.7 180.9 1520 10,480 Feed Water 23 Heated109,900 lb/hr 1,730 1050 565.6 177 1,220 Compressed Air 12 Heated Fuel 31,730 lb/hr 827.4 1050 565.6 177 1,220 Mixture 9 Syngas 141,630 lb/hr3,155 2237 1,225 167 1,151 Generated within Injection Reactor 14 HeatedHeavy 40,000 528.4 500 260 167 1,151 Oil 2 bbl/day Upgraded Heavy722,500 lb/hr 3,754 752.9 400.5 160 1,103 Oil 3 Cooled Upgraded 722,500lb/hr 3,754 120 48.9 112.5 776 Heavy Oil 4 Liquid Product 66 576,800lb/hr 1,427 118.9 48.3 14.8 102 Sour Crude 65 556,100 lb/hr 961.4 118.948.3 14.8 102 Natural Gas 5 1.0 mscf/day 49.9 69.2 20.7 15.8 109 Inputto Stripping Tower 58 Gas 67 154,400 lb/hr 2,447 110 43.3 45 310Wastewater 22  1,130 414.5 118.9 48.3 14.8 102 bbl/day Exhaust Gas 31015,580 506.3 263.5 14.8 102 from Furnace 17 mscf/day Product Crude 2140,710 870.7 118 47.8 15.8 109 56.6 bbl/day

[0059] Another embodiment is depicted in FIG. 5. In this embodimentinjection reactor 14 in replaced by partial oxidation (POX) reactor 75and upgrade reactor 66. Partial oxidation refers to the process oflimiting the amount of oxygen that is allowed to react with the fuelmixture so as to ensure that the preponderance of the output productsare hydrogen and carbon monoxide, and not carbon dioxide and water. POXreactors are well known in the gas-to-liquids conversion field, as wellas in other fields, and this embodiment provides an example of theimplementation of the PCU process using well-understood commerciallyavailable components. Heated fuel mixture 9 and heated compressed air 12are fed to partial oxidation reactor 75 to generate syngas 76. Hotsyngas 76 is sent through a set of injection nozzles (not depicted)located in upgrade reactor 66. In this embodiment, a high steam tonatural gas ratio is used in heated fuel mixture 9 to keep syngas 76 atan approximate temperature of 1400° F. (760° C.). This prevents hightemperature damage to the flow line and nozzles used to transfer syngas76 to upgrade reactor 66. This approximate temperature is not alimitation of this embodiment, but rather is a function of thetemperature resistance of the materials used to fabricate the componentsof the upgrade facility. Simulations of this embodiment again assume 40%of heated heavy oil 2 reacts with syngas and the remaining 60% is thequenching material. Product crude 21 contains 60.7 mole-percent crackedheavy oil, and has an API gravity improvement of 8.4. TABLE 3 SimulationResults for POX Reactor PCU Process Embodiment of FIG. 5 Oil ProcessFlow Flow Volume Temperature Temperature Pressure Pressure QualityReference Volume Kgmole/hr ° F. ° C. psia Kpa API Heavy Oil 1 40,000528.4 199.5 93.1 169 1,165 32.8 bbl/day Natural Gas 5 20.0 997.9 80 26.7178.5 1,231 Input to Mixer 16 mscf/day Steam 7 150,600 lb/hr 3,792 372.8189.3 178.5 1,231 Heated Boiler 930,000 lb/hr 23,420 450.1 232.3 152010,480 Feed Water 23 Heated 154,200 lb/hr 2,429 800 426.7 177 1,220Compressed Air 12 Heated Fuel 188,050 lb/hr 4,790 800 426.7 177 1,220Mixture 9 Syngas 76 342,250 lb/hr 8,223 1401 760.8 167 1,151 HeatedHeavy 40,000 528.4 500 260 167 1,151 Oil 2 bbl/day Upgraded Heavy853,500 lb/hr 8,751 792.5°F 422.5 160 1,103 Oil 3 Cooled Upgraded853,500 lb/hr 8,751 120 48.9 112.5 776 Heavy Oil 4 Liquid Product 66626,400 lb/hr 4,356 119.7 48.7 14.8 102 Sour Crude 65 484,500 lb/hr818.1 119.7 48.7 14.8 102 Natural Gas 5 910 kscf/day 45.4 69.2 20.7 15.8109 Input to Stripping Tower 58 Gas 67 233,400 lb/hr 4,490 110 43.3 45310 Wastewater 22  9,538 3,499 119.7 48.7 14.8 102 bbl/day Exhaust Gas520.0 25,900 507 263.9 14.8 102 from Furnace 17 mscf/day Product Crude21 40,170 806.4 119.5 48.6 15.8 109 API = bbl/day 41.2

[0060] The embodiment depicted in FIG. 6 is similar to the embodiment ofFIG. 5, except that a portion of fuel gas 19 is recycled to upgradereactor 14. Since fuel gas 19 contains reactive gases, hydrogen, andcarbon monoxide, this embodiment has a reduced the demand for naturalgas 5 within fuel mixture 9. After fuel gas 19 is compressed incompressor 71, steam is mixed in mixer 70 with fuel gas 19 to mitigatemetal dusting corrosion in furnace 77. Mixture 72 is heated in furnace77 to a temperature preferably in the range 1000 to 1500° F. (538 to816° C.), and more preferably in the range of 1200 to 1400° F. (649 to760° C.), and mixed with syngas in mixer 69. In this embodiment, anyamount, but preferably from 0 to 70%, of fuel gas 19 can be recycled tomixer 70. Simulations again assumed 40% of heated heavy oil 2 reactswith syngas and the remaining 60% is the quenching material.

[0061] Table 4 shows that the usage of natural gas 5 is reduced by 45%due to the simulation's recycling of 50% of the fuel gas 19. This inturn reduces heated compressed air 12 and steam 7 volume requirements.Those reductions in turn lead to the benefits of reducing exhaust gasemissions from furnace 17 and of lowering the wastewater 22 volume.Product crude 21 contains 61.9 mole-percent of cracked heavy oilcomponents. An alternative process scheme based on this embodiment wouldallow the recycled fuel gas to bypass the gas-treating unit. Thisalternative would have the advantage of a smaller gas-treating unit andwould allow reactive hydrogen sulfide and hydrogen radicals in theuntreated fuel gas to aid the upgrade reactions. TABLE 4 SimulationResults for POX Reactor and Recycled Gas PCU Process Embodiment of FIG.6 Oil Process Flow Flow Volume Temperature Temperature Pressure PressureQuality Reference Volume Kgmole/hr ° F. ° C. psia Kpa API Heavy Oil 140,000 528.4 199.5 93.1 169 1,165 32.8 bbl/day Natural Gas 5 10.5 521.680 26.7 178.5 1,231 Input to Mixer 16 mscf/day Steam 7  78,730 lb/hr1,982 372.8 189.3 178.5 1,231 Heated Boiler 579,000 lb/hr 14,580 596.3313.5 1520 10,480 Feed Water 23 Heated  80,630 lb/hr 1,270 800 426.7 1771,220 Compressed Air 12 Heated Fuel  98,300 lb/hr 2,504 800 426.7 1771,220 Mixture 9 Syngas 76 178,900 lb/hr 4,299 1401 760.8 167 1,151Recycled Tail 174,300 lb/hr 3,383 1401 760.8 167 1,151 Gas Heated Heavy40,000 528.4 500 260 167 1,151 Oil 2 bbl/day Upgraded Heavy 864,400lb/hr 8,209 797.6 425.3 160 1,103 Oil 3 Cooled Upgraded 864,400 lb/hr8,209 120 48.9 112.5 776 Heavy Oil 4 Liquid Product 66 617,100 lb/hr3,990 119.1 48.4 14.8 102 Sour Crude 65 490,100 lb/hr 849.8 119.1 48.414.8 102 Natural Gas 5 910 kscf/day 45.4 69 20.7 16 109 Input toStripping Tower 58 Gas 67 255,700 lb/hr 4,333 110 43.3 45 310 Wastewater22  8,417 3,088 119.1 48.4 14.8 102 bbl/day Exhaust Gas 297 14,780 504.5262.5 14.8 102 from Furnace 17 mscf/day Product Crude 21 40,680 832.5117.5 47.5 14.8 109 41.9 bbl/day

[0062] It should be understood that the preceding is merely a detaileddescription of specific embodiments of this invention. Other embodimentsmay be employed and numerous changes to the disclosed embodiments may bemade in accordance with the disclosure herein without departing from thespirit or scope of the present invention. For example, each of the aboveembodiments involve the use of a single injection reactor or upgradereactor. The PCU process is not so limited. In particular, embodimentsof the PCU process in which more than one injection or upgrade reactorare deployed in a series sequence, to thereby facilitate high upgradeefficiencies. The PCU process may also be employed in embodiments inwhich more than one injection or upgrade reactor are deployed inparallel, so that a higher volume heavy oil upgrade throughput may beattained. Each of these embodiments is within the scope of the presentinvention. The preceding description, therefore, is not meant to limitthe scope of the invention. Rather, the scope of the invention is to bedetermined only by the appended claims and their equivalents.

We claim:
 1. A heavy oil upgrade method in which at least a portion ofthe heavy oil is treated with a hydrogen-containing gas having atemperature above about 1200° F. (649° C.) for less than 10 seconds. 2.The method of claim 1 wherein the gas is the exothermic product of theignition of an oxidizing agent and a hydrogen-containing fuel.
 3. Themethod of claim 1 wherein the treatment involves the vaporization of aportion of the heavy oil.
 4. The method of claim 1 wherein the treatmentinvolves a predominantly gas phase heavy oil upgrade reaction.
 5. Themethod of claim 1 wherein the treatment is quenched by mixing thetreated heavy oil with an untreated heavy oil.
 6. The method of claim 2wherein the hydrogen-containing fuel is a mixture of natural gas andsteam.
 7. The method of claim 2 wherein the oxidizing agent iscompressed air.
 8. A heavy oil upgrade method comprising the steps of:a) introducing an oxidizing agent and a hydrogen-containing fuel into areactor vessel; b) introducing a heavy oil into the reactor vessel, c)igniting the oxidizing agent and the hydrogen-containing fuel in thepresence of the heavy oil to initiate a predominantly gas phase upgradereaction, and d) quenching the upgrade reaction.
 9. The method of claim8 wherein an un-upgraded heavy oil is used to quench the upgradereaction.
 10. A heavy oil upgrade injection reactor comprising: a) areactor vessel, b) means for inputting a heavy oil, an oxidizing agentand a fuel in separate input streams into the reactor vessel; c) meansproximate to the input means for igniting the fuel with the oxidizingagent in the presence of the heavy oil to thereby initiate a localizedheavy oil upgrade reaction; d) means for inputting a second stream ofheavy oil into the reactor vessel for quenching the upgrade reaction,and e) means for withdrawing an upgraded oil mixture from the reactorvessel.
 11. A heavy oil upgrade ignition injector comprising: a) areaction chamber; b) means for inputting heavy oil, fuel, and anoxidizing agent into a first end of the reaction chamber in separatestreams; and c) means for igniting the fuel and the oxidizing agent tothereby initiate an heavy oil upgrade reaction within the reactionchamber.
 12. The apparatus of claim 11, further comprising means forinputting a reaction quenching heavy oil into the injector proximate tothe location of the upgrade reaction.